False Positives

Marissa
What are the odds of having multiple false positives using multiple brands two months in a row?
 Last month I had two false positives (two different brands)and a late (very heavy)period. Was told via blood test that there was no hCG in my system so it wasn't chemical/ectopic. 
This month took 5 positive HTP's (3 different brands) and was late again. AF just showed up today. 
I do not have PCOS or Endo or anything  like that. 
I'm not on any meds.
I'd like to think I'm capable of peeing on a stick. And I'm not reading them outside the allotted window. 
If I'm doing something wrong or something I'd like to know so I can stop having the joy of seeing a line each month and the crushing agony of defeat when AF shows up.